Her support for the ruling isn’t surprising — Clinton said she was for open borders at one point — but the gutter sniping was telling. The activist judges who based their ruling on their liberal politics instead of the Constitution are the same kind she would appoint to the Supreme Court and all other federal courts if she were in the Oval Office.

Thankfully, she won’t get the chance, a fact reinforced by Trump aide Kellyanne Conway. She fired back at Clinton with her version of “3-0,” tweeting,“PA, WI, MI,” a reference to three formerly blue states, worth 46 electoral votes, that Trump flipped to his column. Touché!

And so it went in Week 3 of the Trump era, with Clinton’s taunt, the court ruling, nonstop demonstrations and congressional hijinks combining to illustrate why Trump’s election was crucial. It was a necessary course correction and a dramatic rejection of an arrogant government that both overreaches and underperforms.

Put another way, the hysterical, hateful reaction in many quarters to everything Trump says and does is absolute proof that the ruling elite deserved a comeuppance. The establishment was drunk on power, political and cultural, and never yielded an inch voluntarily or had the decency to admit error. Its rage reflects its sense of entitlement.

I felt that rage when I got an emailed death threat serious enough to turn over to the police. An NYPD officer taking my complaint quickly understood the point: “Oh, you must be pro-Trump,” she said. “I am, too, and I get into arguments all the time.” At least we got a laugh out of it.

There was no humor for South Carolina Sen. Tim Scott, who felt the rage in the form of racist hate mail. A black conservative and Republican, Scott read aloud on the Senate floor messages he received after supporting Jeff Sessions for attorney general.

He was called a “house Negro,” “a disgrace to the black race” and an “Uncle Tom,” among other vile epithets that included the ­N-word, Scott said. He added, “I just wish that my friends who call themselves liberals would want tolerance for all Americans, including conservative Americans.”

This unhinged rage is the new America — only it’s not new. It was hiding in plain sight, hinted at by the contempt that Hillary Clinton, Barack Obama, tenured radicals, college snowflakes and the Democratic media openly held for those who don’t share their worldview.

Trump’s victory ripped open the vein, but it would have erupted at any Republican president. Modern liberals’ contempt for others is essential to their sense of superiority and justifies violence in the streets, threats and simple rudeness. Contempt for others lets mayors think they can disobey immigration laws and judges think there is no law but theirs.

Still, there are reasons why the Court of Appeals ruling could be a blessing in disguise for Trump. Here are the two biggest.

First, the jubilation among Democrats and their media handmaidens reveals how their hatred for Trump and his supporters overshadows any concern for ­national security. The ruling that the government showed “no evidence” that the travel ban would prevent terrorism is preposterous and should alarm every American.

Any such evidence would be classified and certainly wouldn’t be produced in a hasty, one-hour hearing, which the judges conducted over the telephone. The Constitution and laws give the president wide authority to ­decide whether the entry of “any class of alien” would harm the United States.

Effectively claiming that authority for itself, the court grossly oversteps and obliterates the separation of powers. It also opens itself to public fury if the ruling opens the door to terrorists.

The second benefit is that the ruling offers Trump a sobering lesson about the difficult road ahead. Nothing can be taken for granted and every inch of progress will require intense preparation and a willingness to battle on multiple fronts.

The executive order, though sensible in its goals, was especially vulnerable because it was rushed before Trump’s team was in place. The result was confusion about whether it applied to green card holders and dual citizens, and that ruined implementation at airports here and abroad.

Those are rookie mistakes, driven in part by Democrats’ delaying tactics in confirming Attorney General Sessions and others. Yet that reality only underscores how deep the hostility is and how little room there is for error. The lynch mob can succeed only if the White House provides the rope.

As a candidate and president, Trump has endured slings and ­arrows unprecedented in modern times. The onslaught is also harming America, but the madness will be bearable if he finishes the revolution he started.

A scandal Blas can’t dig out of

The rule of holes applies to Mayor Bill de Blasio: When you’re in one, drop the shovel.

Not Mayor Putz. He keeps digging.

Up to his eyeballs in criminal investigations over slush funds and favors to big donors, de Blasio is planning to raise even more money to pay his defense lawyers.

Get this — his law firm is also a lobbyist that reportedly represents dozens of real estate developers with business before City Hall.

The mayor says the firm, Kramer Levin Naftalis & Frankel, has been racking up costs for months but has not been paid a cent. That means he is deep in debt to a law firm lobbyist.

There are other potential conflicts, too. Is the mayor getting a favorable fee rate? Why would anyone not a personal friend pay his legal bills?

Remember, too, that some fundraising at the heart of the criminal probes allegedly took place in Kramer Levin’s office.

The mayor keeps digging just as he is about to meet with federal prosecutors. He calls the meeting “voluntary,” but that’s probably only technically true.

The meeting could be a last chance to stave off criminal charges. Which is why it makes zero sense for him to add to the smell of corruption with his sketchy legal-bill scheme.

Then again, he is who he is.

Wrong ‘paths’

Responding to no demand, Ohio Gov. John Kasich has written a book. It’s called “Two Paths” and, judging from the blurb, he’s still running for president.

I’ll wait for the movie.

Toast of Tehran

Headline: Millions rally in Tehran, chant “Death to America.”

Translation: Bring back Barack Obama. He gave us everything we wanted.